1. Field of the Invention
The invention relates to devices for preventing the unauthorized coupling of tractors to unattended trailers.
2. Description of the Prior Art
It is well known that the trailers of tractor-trailer rigs are often parked in isolated spots or left unattended. In recent years there has been an increasing problem with the hijacking of such vehicles by unauthorized persons. Aside from the theft prevention problem, there is a further safety problem associated with the naked exposure of coupling pins at loading docks and the like. In these instances it is possible for a tractor to be coupled to a trailer while such trailer is being unloaded by means of a forklift or the like. In such instances severe injury has been inflicted on persons who were unloading a trailer when it was mistakenly pulled away from the dock area.
Thus, there is an acute need in the trucking industry for a simple, safe and reliable device for rendering trailers of tractor-trailder rigs insusceptible to coupling with unauthorized vehicles.